Radiometric Dating
There has been great controversy over the age of the earth. Creationists believe in a young earth, while evolutionists believe in an old earth and one of their primary methods for determining the age of earth is radiometric dating. This method has been so convincing, that it has even persuaded many Christians into believing in an old earth. In this section, mistakes made while using method will be introduced.
How exactly does radiometric dating work?
Certain kinds of atoms are unstable and will decay into other kinds of atoms. Uranium will radioactively decay through a series of steps into a stable element, lead.
Radiometric dating is usually used to date igneous rock (rocks which form when hot material cools and hardens). The radiometric clock starts when a rock cools. It is assumed that during this stage the extreme heat will force the daughter elements to escape. Once the rock cools, it is assumed that no more atoms will escape and any daughter element found will be the result of radioactive decay. The dating process requires measuring how much daughter elements are found and the decay rate. The decay rate is measured in terms of half-life.
Radiometric dating is usually used to date igneous rock (rocks which form when hot material cools and hardens). The radiometric clock starts when a rock cools. It is assumed that during this stage the extreme heat will force the daughter elements to escape. Once the rock cools, it is assumed that no more atoms will escape and any daughter element found will be the result of radioactive decay. The dating process requires measuring how much daughter elements are found and the decay rate. The decay rate is measured in terms of half-life.
Radiometric Dating Assumptions
There are many types of sciences, the two focused in radiometric dating are operational science and historical science. Operational science is a systematic approach to understanding that uses observable, testable, and repeatable experimentation to understand how nature commonly behaves. Historical science is interpreting evidence from past events based on a presupposed philosophical point of view.
Radiometric dating uses both of these types of science (measuring the amount of daughter element in the rock sample is an example of operational science, the conditions present when the rock formed can only be studied through historical science.)
Since radiometric dating uses both of these types of science, we can't directly measure the age of something. A combination of scientific techniques of the present and assumptions of historical science would be needed to estimate the age. There are three critical assumptions that can affect the results during radiometric dating:
Radiometric dating uses both of these types of science (measuring the amount of daughter element in the rock sample is an example of operational science, the conditions present when the rock formed can only be studied through historical science.)
Since radiometric dating uses both of these types of science, we can't directly measure the age of something. A combination of scientific techniques of the present and assumptions of historical science would be needed to estimate the age. There are three critical assumptions that can affect the results during radiometric dating:
- The initial conditions of the rock sample are accurately known.
- The amount of parent and daughter elements in a sample have not been changed by processes other than radioactive decay.
- The decay rate of the parent isotope has remained constant since the rock formed.
To better understand radiometric dating, an hourglass will be used. We can observe an hourglass with sand at the top and bottom, we could easily calculate how long the hourglass has been running. We could calculate how much time elapsed since the hourglass was turned over, based on our estimations on how fast the sand is falling and measuring the sand on the bottom. Our calculations could be correct, but the result entirely wrong. This is because we failed to include the critical assumptions:
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Since the initial conditions were not observed, we must make assumptions. All three of these assumptions can affect our time estimates. If the three critical assumptions are not considered, radiometric dating can give incorrect dates.